Other Possibilities for the Cause of the Extinctions at the K/T Boundary:
Various studies such as oxygen isotope analysis of planktonic and benthic foraminifera (Douglas and Savin 1973), angiosperm leaf physiognomy (Wolfe and Upchurch, 1987) and change in the pollen record (Fredericksen, 1989), concluded that a time of long term climate change was in progress at the K/T boundary (Hallam and Wignall, 1997).
An analysis of the epicontinental marine sections of the K/T boundary concluded that the sea level at the time dropped, followed by a rise (Hallam, 1992).
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